package com.hmdp.service.impl;

import com.hmdp.dto.Result;
import com.hmdp.entity.SeckillVoucher;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisIdWorker;
import com.hmdp.utils.SimpleRedisLock;
import com.hmdp.utils.UserHolder;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.aop.framework.AopContext;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.Resource;
import java.time.LocalDateTime;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {


    @Resource
    private ISeckillVoucherService seckillVoucherService;

    @Resource
    private RedisIdWorker redisIdWorker;

    @Resource
    private StringRedisTemplate stringRedisTemplate;

    @Resource
    private RedissonClient redissonClient;
    /*
    * 实现秒杀下单
    * */

    public Result secKillVoucher(Long voucherId) {
        //1.查询优惠劵
        SeckillVoucher voucher = seckillVoucherService.getById(voucherId);
        //2.判断秒杀是否开始
        LocalDateTime beginTime = voucher.getBeginTime();
        if (beginTime.isAfter(LocalDateTime.now())) {
            return Result.fail("秒杀尚未开始");
        }
        //3.判断秒杀是否结束
        LocalDateTime endTime = voucher.getEndTime();
        if (endTime.isBefore(LocalDateTime.now())) {
            return Result.fail("秒杀活动已经结束");
        }
        //4.判断库存是否充足
        Integer stock = voucher.getStock();
        if (stock < 1)
        {
            return Result.fail("库存不足");
        }

        Long userId = UserHolder.getUser().getId();
       //创建锁对象
       // SimpleRedisLock Lock = new SimpleRedisLock("order:" + userId, stringRedisTemplate);
        RLock lock = redissonClient.getLock("Lock:order:" + userId);
        //获取锁
        boolean isLock = lock.tryLock();
        //判断是否获取锁成功
        if ( !isLock)
        {
            //获取锁失败,返回错误或重试
            return  Result.fail("不允许重复下单");
        }
        // TODO 这里的AopContext是去获取代理对象，不然这里的事务有问题
        //获取代理对象(事务)
        try {
            IVoucherOrderService proxy = (IVoucherOrderService) AopContext.currentProxy();
            return  proxy.creatVoucherOrder(voucherId);
        } finally {
            //释放锁
            lock.unlock();
        }
    }

    @Transactional
    public Result creatVoucherOrder(Long voucherId) {
        //6 一人一单
        Long userId = UserHolder.getUser().getId();

            //6.1查询订单
            int count = query().eq("user_id", userId).eq("voucher_id", voucherId).count();
            //6.2判断订单是否存在
            if (count > 0) {
                //用户已经购买过了
                return Result.fail("每人限一份");
            }
            //5.扣减库存
            boolean success = seckillVoucherService.update()
                    .setSql("stock = stock-1")  //set stock=stock-1
                    .eq("voucher_id", voucherId)
                    .ge("stock", 0).update(); //where voucher_id = ? and stock > 0

            if (!success) {
                return Result.fail("库存不足");
            }
            //6.创建订单
            VoucherOrder voucherOrder = new VoucherOrder();

            //6.1 订单id
            Long OrderId = redisIdWorker.nextId("order");
            voucherOrder.setId(OrderId);

            //6.2 用户id
            voucherOrder.setUserId(userId);

            //6.3 代金券id
            voucherOrder.setVoucherId(voucherId);
            save(voucherOrder);
            //7.返回订单id
            return Result.ok(OrderId);

    }
}
